Control apparatus



0d. 12, 1937. D, H MITCHELL 2,095,936

CONTROL APPARATU S Filed Jan. 8v, 1956 Patented Oct. 12, 1937 lFFIQE CONTROL APPARATUS Donald H. Mitchell, Chicago, Ill., assigner to Galvin Manufacturing Corporation, Chicago, Ill.

a corporation of Illinois Application January 8, 1936, Serial No. 58,161

17 Claims.

This invention relates to control apparatus, and more particularly to control heads including means for indicating the position of the control device operated thereby.

. In the form illustrated, the control head is Y especially suitable for remote control of such apparatus as radio receiving sets, and it is especial- `ly valuable for receiving sets in Vehicles where compact, and especially that they do not project forwardly far from the panel. At the same time itis necessary to have an indicating means which isoperable through the full range of adjustment of the control device, and itis desirable that this indicating means be on a fairly large scale so fastorbe clearly Visible.

iThe :rotating needle-type of indicating means is preferred by many people for this purpose, since the user can tell the position of the tuning means by the angular position of the needle without bothering to read the figures on the scale. At the same time, in order to permit accurate tuning it is desirable that the tuning handle make several revolutions for the one incomplete revolution of the indicating needle. There is, therefore, the problem of providing an adequatespeed reducing drive between the tuning handle and the indicating needle at a minimum Y of cost, but with thorough dependability.

Heretofore it has usually been the practice to provide an ordinary gear `and pinion drive, but to do this with a small number of gears it was necessary to use a large gear on the needle shaft. This complicated the matter of lighting the dial from the rear, since the light would have to be farther away from the axis of the needle than the radius of the gear.. This is especially objectionable where the indicating means projects through the panel, as in the form of control head illustrated.

According to the present invention the problem-is solved by providing a small pinion on the needleshaft which permits the light to be mounted close to this shaft, and driving the pinion by (Cl. 11G-124.1)

a gearsegment which in turn is driven by a worm disc mounted on the shaft of the tuning handle. Thus the connecting means comprises only three inexpensive parts, a Worm disc which may be stamped, a gear segment, and the pinion on the needle shaft. This is obviously both reliable in use and economical to manufacture.

When indicating control heads are rst attached to the controlled device.' the indicator is likely not to be in the position corresponding to the adjustment of the controlled device and it is necessary to move one without moving the other until they are in registry. According to the present invention this may be accomplished in a very convenient manner because of the provision of an inexpensive friction clutch between the worm disc and the control device, the worm disc being accessible for holding it stationary with a screw driver.

Other objects and advantagesof this invention will be apparent from the following description, taken with the drawing, in which:

Fig. 1 is an elevation of the face of the control head.

Fig. 2 is a view of the structure shown in Fig. 1 looking from the opposite direction (the back of the' head) and with the cover plate removed.

Fig. 3 is a horizontal section taken approximately along the line 33 of Fig. 1.

Fig. 4 is a detail vertical section taken substantially along the ,line l-ll of Fig. 2.

Fig. 5 is a detail View of the mounting of the` cover plate l2, and an indicator housing I3,

which parts may be secured together in any convenient manner, as by bent-overlugs as illustrated. Secured on the cover l2, as by upsetting, are two bosses It into which sheaths l? may be secured by set screws as illustrated. A switch and volume control cable I8 may extend through one of the sheaths il while a tuning control or station selecting cable I9 extends through the other.

The cable I9 passes through a sleeve 2|, to the outer end of which is secured a handle 22 by a set screw 23 which'passes through a hole in the sleeve 2|` and engages the cable Il, thus locking the handle 22, the sleeve 2| and the cable I9 so that they all rotate together. The sleeve 2| passes through a boss 26 which is secured to the face of the frame I I by an upset flange as shown. A nut 28 may screw onto the boss 29 to secure the control head to the instrument panel. This nut is preferably beveled as shown to center itself in the hole through which boss 29 passes.

Pivotally carried on the inner end of the sleeve 2| is a disc 3| having a spiral groove 32 therein. This groove may conveniently be formed by a stamping operation. The disc 3| is pressed against a head 34 formed on the sleeve 2| by a horse-shoe shaped crimped washer 36 which fits into an annular groove formed in the sleeve 2|. A washer 38 may be interposed between the clip 36 and the disc 3|, as illustrated. The washer 38 and spring clip 36 constitute a friction clutch between the sleeve 2| and grooved disc 3 I, to permit adjustment of the indicating means with respect to the tuning means, as is described below.

Driven by the disc 3| is a gear segment 4| which is pivoted on a pin 42 riveted to the front face of the frame II. This gear segment has a dog 43 formed on its smaller end as seen best in Figs. 4 and 8, this dog being formed by punching and being shaped to ride in the grooves 32 of the disc 3|. The dog 43 is pressed into these grooves by one or more springs 46 riveted to the gear segment and pressing against a guide bar 41 along which they may slide. Instead of the springs 46 shown in Figs. 2, 3 and 4, there may be a spring 46' as shown in Figs. '1 and 8, which bears against the gear segment at both ends and thus has greater strength than a single spring of the form shown in Figs. 2, 3 and 4.

The guide plate 41 is secured to the frame II by two lugs, one of which, 49, is twisted so that the guide must be turned at an angle in order for this lug to be inserted through the corresponding aperture in the frame II. When the other lug 5| is then bent or sprung intothe corresponding slot 52, in the lower edge of frame II, the twisted lug 49 becomes locked so that the guide plate 41 cannot accidentally be removed.

As seen best in Fig. 2, a rotation of the spirally grooved disc 3| in a counter-clockwise direction as there seen, will cause the lefthand end of the gear segment 4| to ride upwardly as the dog 43 follows the spiral groove 32. In other words, rotation of the disc 32 causes a pivoting of the gear segment 4| about the pin 42.

Meshing with the gear segment 4| is a pinion 55 which of course is rotated by the gear segment 4| as it is pivoted by the disc 3|. The pinion 55 is formed on the inner end of a. rshaft 56 extending through housing IIl and sleeve 58 secured thereto, and carries on its outer end the indicating needle 51. A needle 51 is positioned on the outside of a dial 59 which is secured to a supportmember 6| as illustrated best in Fig. 3. The frame I3 holds the support member 6| in place and holds a transparent window member 62Vin a position to protect the needle 51.

The dial 59 is preferably translucent .except for the characters thereon, and may be illuminated by a bulb 66 carried by a. bushing 61 and held thereon by a split cup 68 forming part of the lamp assembly. Because of the small size of pinion 55 the bulb may be positioned fairly close to the center of the dial 59.

The cable I8 may extend through a bushing 1| and a nut 12 thereon similar to bushing 26 and nut 28. A handle 14 may be secured to the cable by set screws. Of course, if desired, a special terminal or coupler may be provided for the cable I8 and a construction may be used which requires a key for operating an electrical switch to turn on the radio receiver.

For the sake of clarity, the operation of the control apparatus may be briey reviewed: The set is turned on and the volume regulated by turning the handle 14, which is secured to, and turns, the cable I8. The program to be heard is selected by turning the handle y22, which is secured both to the sleeve 2| and the cable I9 extending to the tuning apparatus in the set. The sleeve 2|, in rotating with the cable I9, rotates the spirally grooved disc 3|. As the disc 3| rotates, it pivots the gear segment 4| Vwhich has a dog riding in the groove on the disc 3| It is thus seen that the ratio of movement between gear segment 4| and disc 3| or cable I9 may be varied by substituting different discs having spirals of different pitches. The gear segment 4| drives the pinion 55 and shaft 56 on which is mounted the needle 51 which rotates in front of the dial 59 to indicate the program or frequency for which the receiving set is tuned. Of course, if some other apparatus is controlled, the needle will in like manner indicate the adjustment of said other apparatus. If, after the initial assembly, the position of the needle does not correspond with the adjustment of the control device, correction is easily made by turning the. handle 22 while holding the disc 3| from turning, the spring friction washer 36 permitting this re1- ative movement. The disc 3| may easily be held by inserting the screw driver up through the opening 8|, seen in Fig. 2, and jamming it between the disc 3| and the end wall of the housing.

From the foregoing it is seen that although the apparatus is very reliable and convenient, it is extremely simple and takes up very little space. It makes possible a fairly high gear ratio between the control handle 22 and the needle 51 with a minimum number of parts, and without obstructing the most convenient position for locating the lamp. Furthermore, the gear ratio may be varied simply by the substitution of one part, namely'the disc 3|.

Although but one embodiment of my invention has been herein shown and described, it is to be understood that I am not limited thereby, but limit my invention only by the scope of the claims appended hereto.

I claim:

1. Control apparatus including a rotatable control member, a grooved disc rotating therewith, a pivoted lever having one end riding in said groove, and rotary indicating means driven by said pivoted lever for indicating the position of said control member.

2. Control apparatus including a control member rotatable through several revolutions, and an indicating member rotatable through no more than one revolution and arranged to indicate the position of said control member, said member and saidY means being connected together by means including a. pivoted lever operated by a cam member rotating with said control member.

3. Indicating control apparatus including a translucent dial, a rotating indicating pointer having a wide sweep on said dial, a small pinion rigidly connected thereto, and a lamp close to said pinion for illuminating substantially all of said dial, means for rotating said pinion, and means for operating saidpinion-rotating means and for simultaneously effecting the desired control.

`4. Indicating control apparatus including a translucent dial, a rotating indicating pointer having a wide sweepxon said dial, a small pinion rigidly connected thereto, and a lamp close to said pinion for illuminating substantially all of said dial, a `single member for rotating said pinion, and means rotating as a unit for operating said member and effecting the desired control.

5. Control apparatus including a control memloerrotatable through "several revolutions, and an indicating member rotatable through no more than one revolution and arranged to indicate the position of said control member, said member and said means being connected together by means including a pivoted lever operated by a cam member rotating with said control member, said cam and member being connected through a friction clutch whereby, when desired, they may be rotated differentially.

6. An indicating control head for mounting on an instrument panel of a vehicle for remote control of a radio receiving set, including a needle rotatable about an axis substantially perpendicular to the panel, a housing for said needle adapted to project through said panel, a lamp extending into said housing for illuminating said needle, a pinion adjacent to said lamp and connected to said needle, a gear segment pivoted about an axis substantially perpendicular to said panel, a spirally grooved disc driving said segment and mounted on a control member extending through said panel, and adapted to be connected to said radio receiving set.

'7. Indicating control apparatus including a control member, an indicator therefor, and means connecting the two in driving relationship, including an intermediate member supported on said control member and connected thereto through a friction clutch, and a housing for said apparatus having a Wall closely adjacent to said intermediate member and an opening adjacent said Wall whereby said member may be held stationary with a screw driver jammed between it and the Wall while said control member is rotated.

8. Control apparatus including a rotatable control member, a grooved disc rotating therewith, a pivoted lever having one end riding in said groove, and indicating means driven by said driving means for indicating the position of said control member, said pivoted lever being resiliently urged against the face of said disc.

9. Control apparatus including a rotatable control member, a grooved disc rotating therewith, driving means having a portion riding in said groove, and indicating means driven by said driving means for indicating the position of said control member, said driving means being resiliently urged against the face of said disc.

10. Control apparatus including a rotatable control member, a grooved disc rotating therewith, a pivoted lever having one end riding in said groove, and indicating means driven by said pivoted lever for indicating the position of said control member, said pivoted means being resiliently urged against' the face of said discl by a spring mounted thereon and bearing against an oppositely disposed surface.V

11. A control head for mounting on a. panel having holes therethrough including a frame having bosses secured thereto and adapted to extend through two of said holes, nuts adapted to screw on said bosses and secure said frame to said panel; said'nuts having beveled inner faces for centering said bosses in said two holes, and a control member extending through each of said bosses to be accessible for manual manipulation.

i 12. Control appara-tus including a control member rotatable through several revolutions, and an indicating member rotatable through no more than one revolution and arranged to indiv cate the position of said control member, a spirally grooved disc rotating with said control member, said member and said means being connected together by a speed reducing drive substantially free: from backlash including a pivoted leveroperated by having a dog thereon pressed intol the groove of said spirally grooved disc rotating with said control member.

13. An indicating control head for mounting on an instrument panel of a vehicle for remote control of a radio receiving set, including a needle rotatable about an axis substantially perpendicular to the panel, a lamp on said control head for illuminating said needle, a pinion adjacent to said lamp and connected to said needle, a gear segment in engagement with said pinion pivoted about an axis substantially perpendicular to said panel, and means mounted on a control member extending through said panel and adapted to be connected to said radio receiving set for operating said segment.

14. In a control device, a housing including a face plate, a control knob and an indicating dial on one sidev of said face plate, a control drive shaft for said control knob, indicating means in front of said dial, a driven shaft extending through said face plate to the other side for rotatably mounting said indicating means, a pinion gear on said other side of the face plate in connection with said driven shaft, a rotatable spiral in driving connection with said drive shaft, and a pivoted lever extending from said spiral to said pinion to transmit driving power from said control drive shaft to said driven shaft for moving the indicating means over the dial to indicate the rotated position of the control drive shaft.

15. In an apparatus control device, a mounting plate, a rotatable control shaft carried on said plate for adjustably controlling said apparatus and adapted to rotate through more than one revolution on said adjusting movement, an indicating dial, indicating means adapted for rotary movement over the dial through no more than a single revolution, a driven shaft for said indicating means, and a speed reducing drive from said control shaft to said driven shaft including a spiral on said control shaft, a lever pivoted intermediate said spiral and said driven shaft having means at one end for riding on said spiral and means at the other for driving connection with said driven shaft for rotating said indicating means to show the adjusted position of said apparatus.

16. An indicating control head for mounting on an instrument panel of a vehicle for remote control of a radio receiving .set on said vehicle, including a control member extending through said panel for connection to said radio receiving set, indicating means rotatable about an axis substantially perpendicular to the panel, With said means visible in front of said panel, illuminating means for said indicating means, a pinion connected to said indicating means, a gear segment in engagement with said pinion pivoted about an axis substantially perpendicular to said panel, a spirally grooved disc in driving connection with said control member for driving said gear segment to drive the pinion whereby said indicating including a' spirally grooved plate rotating with said control member, a lever pivoted intermediate said plate and said driven shaft having a portion at one end riding on said plate to pivot the lever upon rotation of the control member, and connecting means at the other end of said lever for a driving connection with said driven shaft to rotate said driven shaft and the connected indicator.

DONALD H. MITCHELL. 

